Static pressure measurement…
With the addition of the Shadow Wings 2 tests, you now have a full overview of the features of all unlit BeQuiet! fans in 120 mm format. Shadow Wings 2 is between Silent Wings 3 and Pure Wings 2 in terms of both price and design. In terms of efficiency, they are closer to the more expensive Silent Wings 3 and in certain situations they give top-notch results. Given the lower price, this can be a very attractive option, but there are some things to look out for.
Static pressure measurement…
Finally, it is time to move further down the tunnel a bit. Just behind the fan is a static pressure sensing probe. Its position has been chosen with maximum measurement efficiency in mind. In other words, the sensors are placed at the points of highest pressure (although this is virtually the same everywhere in the unconstrained part of the tunnel).
The Fieldpiece ASP2, which is connected to the Fieldpiece SDMN5 manometer, is used to measure the static pressure in the tunnel. The latter also allows measurements in millimetres of water column, but we measure in millibars. This is a more finely resolved base unit for this meter. And only from there we convert the measured values into mm H2O to allow easy comparison with what the manufacturers state.
While we wrote when measuring noise levels that our results could not be compared with the parameters, that is no longer the case here. As long as the fan manufacturers do not embellish the parameters, they should quote approximately the same pressure values as our tests show. The most significant deviations can only arise at the level of varying accuracy of the measuring instruments, but these are negligible percentages.
The greater the difference between the manufacturer’s claimed values and ours, the less the specifications correspond to reality. If the claimed values are significantly higher, it is certainly an intention to artificially give an advantage to the fans on the market. However, if the manufacturer quotes a lower pressure value than we do, it points to something else. Namely, a weaker tightness of the measuring environment. The less tight the tunnel is, the lower the pressure you naturally measure. This is one of the things we tuned for an extremely long time, but in the end we ironed out all the weak spots. Whether it’s the passage for the probe itself, the flanges around the anemometer, even the anemometer frame itself, which is made up of two parts, needed to be sealed in the middle. Finally, the flap at the tunnel outlet must also be perfectly tight. That’s because static pressure has to be measured in zero airflow.
But there is one thing that often lowers the pressure of the fans a bit. And that’s protruding anti-vibration pads in the corners or otherwise protruding corners. In other words, when the fan doesn’t fit perfectly to the mounting frame at the inlet, and there are small gaps around the perimeter, that also affects what you measure. But we have not gone into this because it is already a quality feature of the fan. In the same way, it will “stand out” and perform a bit weaker than it has the potential to do with better workmanship, even after application by the end user.
- Contents
- BeQuiet! Shadow Wings 2 (BL085) in detail
- The basis of the methodology, the wind tunnel
- Mounting and vibration measurement
- Initial warm-up and speed recording
- Base 6 equal noise levels…
- ... and sound color (frequency characteristic)
- Static pressure measurement…
- … and airflow
- Everything changes with obstacles
- How we measure power draw and motor power
- Measuring the intensity (and power draw) of lighting
- Results: Speed
- Results: Airlow w/o obstacles
- Results: Airflow through a nylon filter
- Results: Airflow through a plastic filter
- Results: Airflow through a hexagonal grille
- Results: Airflow through a thinner radiator
- Results: Airflow through a thicker radiator
- Results: Static pressure w/o obstacles
- Results: Static pressure through a nylon filter
- Results: Static pressure through a plastic filter
- Results: Static pressure through a hexagonal grille
- Results: Static pressure through a thinner radiator
- Results: Static pressure through a thicker radiator
- Results: Static pressure, efficiency by orientation
- Reality vs. specifications
- Results: Frequency response of sound w/o obstacles
- Results: Frequency response of sound with a dust filter
- Results: Frequency response of sound with a hexagonal grille
- Results: Frequency response of sound with a radiator
- Results: Vibration, in total (3D vector length)
- Results: Vibration, X-axis
- Results: Vibration, Y-axis
- Results: Vibration, Z-axis
- Results: Power draw (and motor power)
- Results: Cooling performance per watt, airflow
- Results: Cooling performance per watt, static pressure
- Airflow per euro
- Static pressure per euro
- Results: Lighting – LED luminance and power draw
- Results: LED to motor power draw ratio
- Evaluation
Which Fan would you recommend to use as 3x Intake and Rear Exhaust on the Corsair 4000D between the Shadow Wings 2(BL085), Pure Wings 2(BL039) and Light Wings(BL072)? I’m having a Hard time deciding.
Have you seen our Light Wings (BL072) tests? We published them later than the tests of Shadow Wings 2 (BL085) and Pure Wings 2 (BL039), so their results are missing in the graphs of this article. But you can find them in this one.
The behaviour of all three fans will be very similar in your case, both performance-wise and acoustically. Nevertheless, the Pure Wings 2 is the model that achieves the lowest airflow at equal noise level, but it is also the cheapest… If you are also considering the Light Wings (BL072), I assume you have a higher budget and at the same time we might not care so much about the ARGB LEDs (since you are also deciding between unlighted fans)? In that case I find Shadow Wings 2 (BL085), with which you will not get worse results, the most attractive option. The argument for Light Wings (BL072) could be a wider speed range with lower minimum speeds. Shadow Wings 2 (BL085) start from almost 500 rpm. If you were to run the fans above that anyway, it really doesn’t matter.
I also checked the vibrations, which can, especially in your type of use (on a case), increase the noise, but they are practically zero with the BL085 as well as with the BL072. Personally, I would reach for the Shadow Wings 2 (if you don’t crave the extra low speed of the Light Wings) and enjoy the 40 euros saved. 🙂